Copy array element to standard python scalar

[quant12345]

This PR removes warnings:

DeprecationWarning: Conversion of an array with ndim > 0 to a scalar is deprecated, and will error in future. Ensure you extract a single element from your array before performing this operation. (Deprecated NumPy 1.25.)

Copy array element to standard python scalar. If the array is larger than one element, raise an error.

Test to check:

pytest pandapower/test/control/test_discrete_tap_control.py::test_discrete_tap_control_lv
pytest pandapower/test/control/test_discrete_tap_control.py::test_discrete_tap_control_hv
pytest pandapower/test/control/test_discrete_tap_control.py::test_discrete_tap_control_lv_from_tap_step_percent
pytest pandapower/test/control/test_discrete_tap_control.py::test_discrete_tap_control_hv_from_tap_step_percent
pytest pandapower/test/estimation/test_wls_estimation.py::test_3bus_with_bad_data
pytest pandapower/test/estimation/test_wls_estimation.py::test_cigre_with_bad_data
pytest pandapower/test/grid_equivalents/test_get_equivalent.py
pytest pandapower/test/grid_equivalents/test_get_equivalent_networks.py